| 摘要: | 人類的活動對環境造成影響，土地利用的型態和格局改變，人口密度與不透水鋪面逐年增加，都市化效應則伴隨而生；而溫室氣體的排放造成氣候的變遷，影響了降雨的時空分佈，以水資源的角度來考量，皆會對水文環境造成影響和衝擊，在未來城鎮發展之下，氣候變遷及土地利用變遷對流域的潛在影響，可以做為未來都市發展規劃之參考。
故本研究用土地利用變遷模式CLUE-s、氣象合成模式WGEN、SWAT水文模式，探討土地利用變遷及氣候變遷情境下，流域內河川的逕流量變化。選用新竹鳳山溪流域為研究區域，將土地利用種類分成六種(農業、森林、都市、水利、遊憩、其他)進行討論，並分析土地利用變遷因子，再利用CLUE-s模式模擬出未來土地利用變遷的情況，並設定不同都市化土地利用變遷情境，分別為都市化15%、20%、25%、30%並加上無變遷情境，共有五種土地利用情境；而氣候變遷部分使用TCCIP所提供的第五次報告書中的RCPs情境，選用RCPs中溫室氣體高度排放的情境RCP8.5並加上無變遷情境，共有兩種氣候情境，並將土地利用變遷與氣候變遷情境代入SWAT水文模式，討論在鳳山溪流域在近未來(2030年)時，不同程度的都市化土地利用與氣候變遷之間的關係，探討都市化土地利用變遷與氣候變遷對流域的水文量所帶來的影響。
研究結果顯示氣候變遷改變影響雨量及溫度，對各流量的影響皆隨著情境中雨量成正相關，而土地利用變遷則改變地表的不透水程度，增加地表逕流量，但卻會減少土壤側向流量與地下水流量，然而氣候變遷的影響約為土地利用變遷都市化情境15%~30%的5~22倍，但是本研究認為土地利用變遷的影響還是不可以忽略。
;Human activities, such as the pattern of land use changes, urbanization with the population density and impermeable pavement increased year by year affect the hydrologic environment. On the other hand, greenhouse gas emissions cause climate change, affecting the temporal and spatial distribution of rainfall. From the perspective of water resources, these changes will have impact on the hydrological environment. The identified potential impacts of climate change and land use change on the basin can be used as a reference for future urban development planning. The CLUE-s model, SWAT model and WGEN model were employed to estimate the impacts of hydrological fluxes of Fongshan River basin, given land use changes and climate changes condition projected in 2030. Land use types are divided into six categories, namely agriculture, forest, urban, water conservancy, recreation, and others, to discuss the land use changes. The CLUE-s model was utilized to simulate the future land use change situation. There are five land use programs, namely 15%, 20%, 25% and 30% of urbanization and no change. The climate change component is RCP8.5 with no change scenarios. Two sets of contexts were input into the SWAT model to discuss the relationship between urban land use and climate change in the Fengshan River Basin in 2030. The simulation results show that the climate change affects the rainfall and temperature. The impact of flows is positively correlated with the rainfall in the scenario, which is partially due to urbanization alter the surface impermeability and increases the surface runoff, but reduces the lateral flow of the soil and the groundwater flow. The impact of climate change is 5 to 22 times of 15% to 30% of land use change scenarios. However, this study suggests that the impact of land use change can’t be ignored. |
